Originally Posted by: LordathestringsColours are different wavelengths of light, existing independantly of any observer. However we percieve a particular colour, that perception is consistent, and what you see as 'green' will also be seen as green by someone else. Things get a bit tricky in transistion areas like blue-green, but that's because some people discern small gradations in colour better than others, not because the colour they are looking at is actually different.